In the coming year, studies will be performed in two major areas: (1) The Hre rat is an animal with an inherited disorder of sperm maturation. These animals develop late-onset seminiferous tubular failure which is associated with defective androgen binding protein (ABP) production. These observations suggest that studies of androgen binding protein may provide some insight into the mechanism of oligospermia in this genetic model. Antibodies prepared to homogeneous rat ABP will be used in an immunoprecipitation assay to determine the rates of ABP synthesis and degradation. (2) A unique affinity column was developed for purification of androgen binding proteins. This column will be adapted to studies of androgen receptor activity in kidney nuclei. In addition, an antibody to beta-glucuronidase was prepared and this will be used in an immunoprecipitation assay for studying beta-glucuronidase turnover during androgen treatment. BIBLIOGRAPHIC REFERENCES: Musto, N.A. and C.W. Bardin. Decreased levels of androgen binding protein in the reproductive tract of the restricted (Hre) rat. Steroids 28: 1-11, 1976. Janne, O., L.P. Bullock, C.W. Bardin and S.T. Jacob. Early androgen action in kidney of normal and androgen insensitive (tfm/y) mice: Changes in RNA polymerase and chromatin template activities. Biochem. Biophys. Acta 418: 330-343, 1976.